Grandma and grandpa had six children. each of those children grew up and had four children of their?

All children were female and reproduced via parthenogenesis. So, no fathers except great-grandpa at the table:

Grandma and grandpa (2) had six children(6). each of those children grew up and had four children of their own(4*6). those children all grew up and each one had two children(24*2). everyone came to thanksgiving dinner at grandmas house. how many people will be at the table?

2+6+24+48 = 80 people